Perf::Stopwatch is a Perl Module that can be quickly added and removed from any existing code to debug/optimize portions of code. Example of use are: database calls, loop efficiency, total script time, and webpage timeouts.
the omega xvi project is a javascript debugger written in javascript. it can debug code, execute blocks of code or entire applications, as well as detect variables. because of its javascript nature, it can be run through a webpage, online.